Rapid growth of the mobile platform can have drawbacks, according to an IMS report

Android shipped more than 6 million handsets last year and is forecast to ship more than 20 million handsets in 2010, according to IMS Research. The rapid evolution of Android from version 1.5 to 2.1 has resulted in four different versions of the OS across devices. Fragmentation, can occur when applications written for one version of an OS are not compatible with other versions, IMS said in a statement released about the study this week.

"Typically, platform upgrades occur at a much slower pace and fragmentation is well controlled ," said IMS analyst Chris Schreck, in an interview.

Fragmentation is a concern for developers, according to IMS. Differentiating between strains of OS, modifying codes for each strain, and ensuring that a user obtains the appropriate version of a program are not practical possibilities for many developers.

Having different OS strains limits the potential market for an application, IMS said. The issue of fragmentation extends beyond developers to handset vendors and mobile network operators. The cost of maintaining an OS goes up with each variation that needs to be supported.

Help could be on the way. The continuing maturity of Android is expected to slow the pace of major platform updates, IMS said. Also, there is speculation Google will decouple software updates from mobile network operators, enabling users to upgrade devices directly from the Android Marketplace. It remains to be seen how such changes would rein in Android fragmentation, said IMS.

Another apparently overlooked issue, though, is that the Apache license used to distribute Android does not require licensees to contribute modifications of the platform back to Google. This can encourage licensees to innovate but also is a "recipe for fragmentation," IMS said.

While IMS anticipates considerable market share gains for Android, Google must manage fragmentation or other OSes, such as Symbian or the LiMo Platform, could gain as open source alternatives.